Spawning time and place of the Japanese eel Anguilla japonica in the North Equatorial Current of the western North Pacific Ocean     

Satoshi Ishikawa  Kunihiro Suzuki  Tadashi Inagaki  Shun Watanabe  Yobuo Kimura  Akihiro Okamura  Tsuguo Otake  Noritaka Mochioka  Yuzuru Suzuki  Hiroshi Hasumoto  Machiko Oya  Michael J Miller  Tae Won Lee  Hans Fricke  Katsumi Tsukamoto 《Fisheries Science》2001,67(6):1097-1103

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收获期对杂交早稻品质的影响   总被引：6，自引：1，他引：5  

程建峰  潘晓云  刘宜柏 《江西农业学报》2001,13(2):31-35

研究了不同收获期对杂交早稻稻米品质的影响 ,结果表明 :不同收获期处理间稻米的糙米率、精米率、长宽比、垩白指数及直链淀粉含量均无显著差异 ,但胶稠度及蛋白质含量均存在显著差异 ,以抽穗后 35d收获的稻米胶稠度最高 ,以抽穗后 2 5d收获的稻米蛋白质含量最高  相似文献   

分期播种下拟高粱生育进程的温光特性     

陈才夫  梁祖铎 《草业科学》1992,9(6):27-30

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充足底墒播后不灌水时肥料和播期组合对小麦生长和耗水的影响   总被引：2，自引：1，他引：2  

薛绪掌  王志敏  秦勇 《干旱地区农业研究》2003,21(4):78-83

在充足底墒播后不灌水条件下,进行了适当晚播(10月15日播)与超晚播条件下的小麦肥料试验。主要结果为:(1)播后不灌水条件下超晚播减产严重,主要是单位面积总粒数下降太多,通过适当提高穗密度难以补偿;(2)高施磷条件下(施磷二铵450kg/hm2),随施氮量的增加,开花前的耗水量没有增加,而灌浆期的耗水量则随氮肥用量增加而增加;(3)控制花前无效生长,降低花前耗水,优化开花后的群体结构,提高灌浆期的灌浆强度是降低总耗水、提高水分利用效率的基本途径。  相似文献   

施肥和刈割日期对杂交狼尾草钙、磷、镁含量的影响及其与家畜需要的关系   总被引：7，自引：2，他引：7  

钟小仙  江海东  曹卫星  顾洪如 《草业学报》2005,14(5):87-91

研究了不同施肥处理和刈割日期对杂交狼尾草Ca、P和Mg含量的影响及其与家畜营养的关系,结果表明,有机肥的施用显著降低了植株Ca含量,对植株P和Mg含量无显著影响;随无机氮施用水平的提高,杂交狼尾草植株Ca和Mg含量显著提高,P含量显著降低;植株Ca、Mg含量均随刈割日期的推迟而显著提高,植株磷含量随刈割日期的推迟呈先降后升的规律;根据NRC推荐的饲养标准(奶牛、肉牛和绵羊),所有处理杂交狼尾草植株Mg含量均能满足家畜的需要,Ca:P为(0.95～2.67):1;利用杂交狼尾草饲喂高产奶牛时,应注意日粮中Ca、P的添加.  相似文献   

Effect of Sowing Date on Agronomic Traits and Starch Physicochemical Properties of Proso Millet   总被引：1，自引：1，他引：0  

LUO Yan  QU Yang  YANG QingHua  ZHANG WeiLi  GONG XiangWei  LI Jing  GAO XiaoLi  GAO JinFeng  YANG Pu  WANG PengKe  FENG BaiLi 《中国农业科学》2019,52(22):4154-4165

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不同播期对黄秋葵长势、抗病性和产量的影响     

宋聚红  吴然  王海山  刘玉芹 《蔬菜》2019,(1):23-31

为在河北省推广种植黄秋葵,在安国、保定、邯郸、衡水和石家庄5个试验点进行黄秋葵分期播种试验,研究了不同播期对石秋葵1号、红玉和五福3个品种生长势、抗病性和产量的影响。结果表明:播期对石秋葵1号、红玉和五福生长势、抗病性和产量具有较大的影响,随着播期的推迟,3个品种的茎粗大致呈逐渐增高的趋势,株高呈先降后升的趋势(除2018年的红玉外),单株结果数则先增加后减少,单果质量(除五福外)逐渐增大;以4月20日、25日和30日为播期,得到的黄秋葵单株产量和折合667 m~2产量较高。综合得出,河北省黄秋葵种植以4月20日、25日、30日为播期最为适宜。  相似文献   

Relevance of Osmotic and Frost Protecting Compounds for the Winter Hardiness of Autumn Sown Sugar Beet          下载免费PDF全文

J. Loel  C. M. Hoffmann 《Journal of Agronomy and Crop Science》2015,201(4):301-311

The cultivation of autumn sown sugar beet (winter beet) is supposed to result in a marked yield increase compared with spring sown sugar beet. Although the importance of the growth stage reached before winter for the survival of autumn sown sugar beet has already been shown, it is not clear to which extent osmotic and potentially frost protecting compounds may contribute to winter hardiness. The study thus aimed to analyse the acclimatization process of sugar beet to low temperatures and to identify compounds which are important for survival of frost. Field trials with autumn sown sugar beet were conducted at eleven environments in Germany from 2009/10 to 2012/13, which were accompanied by greenhouse experiments with controlled temperature regimes. In the field trials, the survival rates after winter varied from 0 % to 99 %, but only in four environments differences between the five genotypes occurred. During acclimatization, betaine, glutamine, proline and raffinose were markedly accumulated and osmolality was enhanced. In particular betaine, amino acids and osmolality showed a positive correlation to the survival rate and were thus identified as potentially frost protecting substances for sugar beet. In contrast, raffinose and proline seem to act rather as stress indicators as they were negatively related to survival. Possible frost protecting substances were identified which can be used in breeding to improve the winter hardiness of sugar beet.  相似文献   

密度和播期对杂交玉米遵糯4号鲜穗数的影响     

伍名龙  龙正凯  舒中兵  段明禹 《现代农业科技》2015,(12):14-15

采用206最优回归设计方案,研究了不同密度和播期对遵糯4号鲜穗数的影响。结果表明:在试验设置的密度和播期范围内,随二因素升高,鲜穗数先升后降。综合考虑,密度在55 500~64 500株/hm2、播期在4月12—18日水平区间内,有利于遵糯4号鲜穗数的提高。  相似文献   

Estimation of Crown Temperature of Winter Wheat and the Effect on Simulation of Frost Tolerance          下载免费PDF全文

T. Persson  A. K. Bergjord Olsen  L. Nkurunziza  E. Sindhöj  H. Eckersten 《Journal of Agronomy and Crop Science》2017,203(2):161-176

Accurate estimation of winter wheat frost kill in cold‐temperate agricultural regions is limited by lack of data on soil temperature at wheat crown depth, which determines winter survival. We compared the ability of four models of differing complexity to predict observed soil temperature at 2 cm depth during two winter seasons (2013‐14 and 2014‐15) at Ultuna, Sweden, and at 1 cm depth at Ilseng and Ås, Norway. Predicted and observed soil temperature at 2 cm depth was then used in FROSTOL model simulations of the frost tolerance of winter wheat at Ultuna. Compared with the observed soil temperature at 2 cm depth, soil temperature was better predicted by detailed models than simpler models for both seasons at Ultuna. The LT50 (temperature at which 50 % of plants die) predictions from FROSTOL model simulations using input from the most detailed soil temperature model agreed better with LT50 FROSTOL outputs from observed soil temperature than what LT50 FROSTOL predictions using temperature from simpler models did. These results highlight the need for simpler temperature prediction tools to be further improved when used to evaluate winter wheat frost kill.  相似文献